function sequentialSearch(arr,item){
    arr.forEach((value,index) => {
        if (item === value){
            console.log(index);
        }
    })
    let array = arr.entries();
    for (let i of array){
        if (item === i[1]){
            console.log(i[0])
        }
    }
}

sequentialSearch([1,2,3,4],3);

